Primer assembly



May 10, 1955 c. H. JORGENSEN ETAL 2,707,921

PRIMER ASSEMBLY 2 Sheets-Sheet l 1 Filed NOV. 28, 1950 mm, .N R wm mHJmw. .N .QQ ma m 5 m" w Am. n mm mv n" E n am. M 4 QS .,A/. cy n .p l v H\\VVVI\\\\\\\\\\\\\\\\\\\\\ WB A MW May 10, 1955 c. H. JORGENSEN ET AL2,707,921

PRIMER ASSEMBLY 2 Sheets-Sheet 2 Filed NOV. 28, 1950 I4 h n INVENTOR.CLARENCE H. JORCENSEN AND CLARENCE H. JORCENSEN JR T'l/E/R ATTORNEYUnited States pas PRIMER ASSEMBLY Clarence H. Jorgensen and Clarence H.Jorgensen, Jr., East Rochester, N. Y.

Application November 28, 1950, Serial No. 197,954

6 Claims. (Cl. 10S-153) This invention relates to primer devices orpumps and has particular reference to manually operated priming pumpsfor use with internal combustion engines for injecting or sprayinggasoline or other liquid fuel into the intake manifold so that thestarting of the engine may be easily and quickly accomplished. Moreparticularly this and asV the leakage is'y not uniform due to thevariations in the; manifold vacuum, it is impossible to maintain anefficient as well as a correct carburetor adjustment at all enginespeeds. Moreover, this leakage often results in morev fuel being drawninto the cylinders than will be burned therein and as aresult the excessfuel seeps downwardly past the piston rings and into the lubricatingoil, destroying its value for lubricating purposes and causing excessivewear of the piston rings and bearings, and the scoring of the cylinders,with the consequent damage to the engine'and loss of power.

PrimerI pumps of known construction have the further disadvantages inthat when connected to a source of liquid fuel supplied under pressureby a fuel pump, as is commonly the caseA with the present day internalcombustion engines, the pressure of the` incoming fuel tends tocauseobjectionable leakage around the outer or handle end ofthe primerplunger which not onlywastes the fuel, but also presents a distincthazard to the health and safety of the operator.

A further disadvantage of primer pumps of known construction is that dueto the solvent action of the gaso-v line or other iluid pumped, thelubricating film between the piston and. cylinder is quickly dissolved,making it diflicult, if; not impossible to maintain the properlubrication therebetween.

One. object' of the present invention is to provide an improved` primerpump having a more simple, practical and eflicient construction.

Another objecty is to` provide a primer pump having animprovedconstruction and a more practicalv arrange ment ofi parts sothat there is no possibility of fluid or air being drawn. into thecylinders by the suction of" the engine.

Another object is to provide a primer pump having the above advantages,adapted to be connected to a supply of fluid under pressure, and havingimproved piston and inlet construction whereby the fluid pressure uponthe opposite ends of the piston is equalized so that the piston remainsinthe normal inward or closed position thereof.

Another object is to provide a primer pump of the above nature having animproved piston and inlet construction which prevents the fluid fromleaking outwardly 2,707,921 Patented May 10, 1955 along: the plungerinto the operators compartmentor cockpit.

A further object is to provide a primer pump of the above nature havingan improved cylinder and inlet port construction whereby the Wall of thecylinder is smooth and free from sharp edges adjacent the inlet forpreventing damage to the piston as it is moved past the inlet.

Still a further object is to provide a primer pump having the aboveadvantages in which the source of lubrication for the piston andcylinder is protected against contact with and dissolution by the fluidbeing'pumped.

To these and other ends of the invention resides in certain improvementsand combinations of parts, all as will be hereinafter more fullydescribed, the novel features being pointed out in the claims at the endof the specification.

In the drawings:

Fig. l is a perspective view of an automobile engine and a primer pumpembodying the present invention showing the connections therebetween;

Fig. 2 is a side elevation, partly in section, of the above primer pumpshowing the piston in the normal inward or closed position thereof;

Fig. 3 is a plan view, partly in section, as indicated by section line 33 in Fig. 2, showing the piston in the outer position thereof;

Fig. 4. is a sectional end elevation substantially along line 4 4v inFig. 2, showing the spring actuated diaphragm in closed position, and

Fig. S is an enlarged sectional elevation substantially along line 5-5in Fig. 3 showing the circumferentially spaced inlet ports.

The embodiment of the invention herein disclosedI by way of illustrationcomprises, preferably, a primer-pump shown generally at (Fig. l)connected at the discharge iitting thereof toa pipe 17 and at the inletfitting thereof to a second pipe 19. Intake pipe 19 is connected at itsopposite end to a T' fitting 2l located in a fuel line 23 which leads.from the discharge side of a fuel pump to a carburetor 27. Fuel pump 25is connected to a supply of liquid fuel by a pipe 29. Carburetor 27 isconnected by av flanged coupling 31 to anl engine intake manifold 33which is secured to an engine 3'5 bysuitable means (not shown), as wellunderstood in the art.

Thus, the fluid in intake pipe 19 is under pressure whenever fuel pump25 is operating and when the primer pump; piston, shown generally at 37(Fig: 2),. iS moved outwardly from the position as shown inv Fig. 2 tothat as shown in Fig. 3, the liuid quickly lls the volume di`s' placed'by said piston movement and upon the return of said pistonA to itsinitial position, the fluid is forced out-v wardly through dischargepipe 17, by meansv to be hereafter moreV fully described, and entersintake manifold 33 preferably through suitable vaporizing or jetfittings 39, 41 and 43 as well understood in the art.

The primer consists of a body member 45 (Figs. 2 and 3) preferablyformed by a die-casting of brass or other suitable material and has acylindrical threaded socket or bore- 47 (Fig. 2) in one side thereof. Acylindrical member 49 is threadedly mounted in socket 47 as; shown inFigs. 2 and 3 and is adapted to slidably receive the cooperating piston37, to be hereafter more fully de` scribed'. The outer end 5l ofcylindrical member 49 isexternally threaded and has a check nut 53positioned thereon with a threaded member 55 onthe outer end of thevmember for clamping said primer to the instrument board or othersuitable support 57.

The primer has an inlet or intake means comprisingan internally threadedprojecting nipple 59' (Fig. 2) located in the lower side of body chamber45 as viewed: inFig.. l` and opening at the inner end thereof intosocket 47'. A screw threaded fitting 6l (Fig. 2) is positioned within 3nipple 59 and is connected to supply pipe 19 as shown in Fig. l. Fitting61 has a bore 63 extending therethrough and an enlarged chamber 65 inthe inner portion thereof for receiving an inwardly opening springactuated ball check valve 67 for preventing tinid flow outwardly throughsaid fitting 61 as well understood in the art. A port 69 (Figs. 2 and 5)is provided at the bottom or inner end of nipple 59 which is in registerwith one of a series of circumferentially spaced ports 71 (Fig. 5)opening through the walls of cylindrical member' 49, as shown in i Figs.3 and 5.

The circumferentially arranged ports 71 are so spaced that the distancebetween two adjacent ports is less than the width of the inner end ofport 69, as shown in Fig. 5, so that regardless of the rotary positionof said cylindrical member 49, at least one of said ports will be inpartial or complete register with the inner end of port e9. it isimportant that the internal surface of cylindrical member 49 is smoothand free from sharp or rough edges which would cut into and damage thepiston packing rings, to be hereafter described. 1n order to prevent theformation of any rough or sharp edges at the intersection of the innerends of ports 71 and the internal surface of cylindrical member 49, saidports are formed by drilling a series of holes 72 which extend inwardlypartway through the walls of the cylindrical member 49. This leaves athin portion adjacent the inside surface of the cylinder walls throughwhich is drilled a second and smaller hole, thereby forming at the innerends of ports 71 oppositely extending lip portions 73. Lip portions 73are formed or pressed outwardly into holes 72, by suitable means,thereby providing a smooth and. unbroken transition between the internalsurface of cylindrical member 49 and ports 71.

A spacing washer 74 positioned at the inner end of socket 47, serves asa stop for the inward movement of cylindrical member 49. Washer 74 alsoserves as stop for the inward movement of piston 37 so that when saidpiston is in the normal inward or closed position thereof, ports 71 aresubstantiailly opposite the center of said piston, for reasons to behereafter explained.

Said primer is provided with outlet means which connects socket 47 tothe engine intake manifold 33 by discharge pipe 17. Said outlet meanscomprises a bore 75 (Fig. 3) extending longitudinally through bodymember 45 and opening in the inner end thereof into the inner end ofsocket 47 as shown in Fig. 3. Bore 75 is enlarged adjacent the outer endthereof and has a spring actuated hail check valve 77 positioned thereinwhich prevents fluid from entering socket 47 through bore 75. Theenlarged outer end of bore 75 is internally threaded for receiving ascrew 79 which adjusts the tension on valve spring 81 as well understoodin the art.

A port 83 (Figs. 3 and 4) connects the outer portion of bore 75 with asecond chamber, located in body member 45 and shown generally at 85(Fig. 4). is preferably divided into lower and upper chambers 87 and 89(Fig. 4), respectively', by a flexible diaphragm 91 of known andsuitable material, as for example, neoprene, which extends across saidchamber and which is held in position by a threaded cap 93 screwed intobody member 45 as shown in Fig. 4. A washer 95 (Fig. LE) is positionedbetween cap 93 and diaphragm. 91. A discharge fitting 97 threadedlyengages body member 45 and extends upwardly into the lower portion S7 ofchamber 55 as shown in Fig. 4. Cap 93 is centrally formed with arecessed chamber 99 which serves as a seat for one end of a spring 101,the other end of which embraces a member 103 having a curved base flange195 which is in engagement with the upper side of diaphragm 9.1 andforces said diaphragm over the correspondingly curved inner end oftitting 97, thereby sealing said fitting and closing said outlet means.Cap 93 has an air vent 197 in the center thereof, and as fitting 97 isconnected to the engine intake manifold by pipe 17, it is evident thatthe suction of the engine Chamber 35 will aid spring 191 in normallyseating diaphragm 91 over the inner end of bushing 97.

We also provide a novel piston 37 which is adapted to closely titcylindrical member 49, as well understood in the art and which isfastened to the inner end of a longitudinally extending rod or plunger199 by a nut 111 (Fig. 2). Rod 109 has at the opposite end thereof ahand knob 113. Piston 37 has adjacent the inner end thereof acircumferentially extending groove 115 and a similar circumferentiailyextending groove 117 spaced inwardly a short distance from the outer endthereof. Grooves 115 and 117 form seats for positioning packing rings119 and 121, respectively, which, known in the art as O rings, arecircular in cross section, and are composed of known and suitablematerial, as for example, synthetic rubber.

it is evident from the above description of our improved piston thatwhen the piston is in the normal inward or closed position thereof, asshown in Fig. 2, the inlet ports 71 are approximately opposite thecenter or midpoint of the piston. Thus, the pressure of the tluid inchamber 65 and the aligned ports 69 and 71 acts with equal force againstpacking rings 119 and 121 adjacent the inner and outer ends,respectively, of the piston. As these forces act longitudinally alongthe piston parallel to the direction of movement thereof, and are equalin magnitude, they tend to hold the piston in its normal closedposition, until pulled outwardly by the operator, thereby eliminatingthe objectionable characteristic of prior pumps in which the pistontended to work outwardly due to the uid pressure thereon.

A further advantage of our construction is that with the piston 37 inthe normal closed position thereof, packing ring 119 effectivelyinterrupts and seals od the fluid connection between the inlet andoutlet of the pump and thus is a further safeguard against leakage offuel or air through the primer into the engine. Packing ring 121, on theother hand, prevents the tiuid from escaping outwardly along piston 37and thus eliminates the danger of fuel leakage along the piston rod intothe operators compartment or cockpit and at the same time prevents thefuel being pumped from contacting the lubricating means, to be hereafterdescribed.

A common difculty with primer pumps of this nature has been in providingthe proper lubrication between the piston and cylinder, when used withsolvent fuels such as gasoline, which tend to dissolve or wash thelubricant away from both the cylinder walls and piston and todeteriorate the lubricating means ali of which resulted in undesirablewearing of the piston and cylinder. We provide a novel self-lubricatingmeans which, in conjunction with our improved piston and packing,provides proper lubrication regardless of the fuel being pumped.

Piston 37 is reduced in diameter adjacent the outer end thereof as at123 to form a seat for positioning three lubricant impregnated washers125, preferably of hard felt or other suitable material, which, as thepiston is reciprocated, apply a thin coating of oil, graphite, or otherknown and suitable lubricant to the inner surface of cylindrical member49. Washers 125 are prevented from moving inwardly along piston 37 by aradially projecting ridge 127, which separates said washers from outerpacking ring 121. Washers 125 are prevented from moving outwardly by ametallic washer 129 which is held in position against the outer end ofpiston 37 by a shoulder on piston rod 109. A gasket 131 (Fig. 2) ofknown and suitable material, preferably synthetic rubber, is positionedadjacent the outer end of piston 37 for preventing leakage betweenpiston rod 109 and piston 37.

Thus, it is evident that our improved piston not only as the advantagespointed out above, but also that said piston prevents the fluid beingpumped from contacting the lubricating washers or rings 125, therebypreventing both the deterioration of the washers and the washing away ofthe lubricating material. Although a small amount of fluid is trappedbetween packing rings 119 and' 121 and willbe: carried back and forth bythe piston and will initially remove a certain amount of the lubricantfrom the cylinder Walls, it is to be. noted that this fluid is small inquantity and tends. to become saturated with the lubricant and lose itsability to` further dissolve the lubricant` so that thereafter thelubricating film is substantially unimpairedv by the contact with thistrapped fluid.

In operation, therefore, with the primer connected to the source of.fuel and. engine manifold as shown in Fig. 1, it is only necessary topull knob 113 outwardly moving piston 37 to the right from its positionas shown in Fig. 2 to its position as shown in Fig. 3, whichcauses asupply ofiluid to flow through the inlet` check valve. 67 into thecylinder of the pump. Thereupon the piston isr pushed inward by theoperator, increasing the pressure in` the pump and forcing ball valve 67against its seat. This increased pressure forces the fluid through bore75 to open valve 77 and through port 83 into the lower portion 87 ofchamber 85. The huid spreads out underneath the diaphragm 91 in chamber85 with the effect of hydraulic action thereon and forces diaphragm 91away from the inner end of fitting 97 against the combined action ofspring 101 and suction of engine 35, if running. This allows the primingfluid to pass outwardly through discharge pipe 17 and into the manifoldof the engine.

It will thus be understood that the forcing of the liquid into the lowerportion of chamber 85 underneath diaphragm 91 unseats the diaphragm andallows the uid to pass through the primer and into the engine, andthereafter the diaphragm is seated by the combined action of spring 101and the suction of the engine, if running, so that the primer is sealedagainst leakage of air or fuel into the engine except when the huidpressure beneath diaphragm 91 is made to exceed the above combinedpressures. This occurs only when piston 37 is moved inwardly from rightto left in the above pumping stroke.

It is evident that the greater the suction of the engine, the greaterwould be its tendency to open outlet check valve 77 and draw in fluidfrom the primer. However, this tendency is counteracted by the fact thatgreater engine suction serves to increase and improve the sealing actionof diaphragm 91 and thus the sealing action of the diaphragm varies tomatch the varying tendency of the engine to draw in excess fluid throughthe pump. In addition to the above suction action, diaphragm 91 is heldin sealing engagement by spring 101 so that at full throttle operation,when the suction is at a minimum, diaphragm 91 is still held in sealingengagement with discharge bushing 97.

If for any reason, such as high altitude or low temperature operation,either the inlet or outlet check valve spring break, it would not affecteither of the three remaining sealings, and even if all of the springsshould fail, packing rings 119 would still prevent leakage through thepump into the engine at all speeds, and diaphragm 91 would still exert asealing action in proportion to the suction of the engine. Thus, theabove primer is especially well adapted for use in aircraft or similarvehicles where fuel economy, reliability and safety of operation are ofprimary importance.

It will be understood that in certain installations it may be desirableto omit diaphragm 91 and spring 101. Although this removes one safetyfeature, the function of which is to prevent fuel or air from beingdrawn through the primer, it does not mean that the suction of theengine will now be resisted only by the tension within outlet valvespring 81. If, under the above circumstances, the engine suctionsucceeds in opening outlet valve 77, it will then act directly againstthe inner end of piston 37 and will in effect tend to draw the pistonmore tightly into the closed piston, in which position packing ring 119effectively interrupts and seals oif the fluid connection between theinlet and outlet of the pump thereby preventing the engine from drawingfuel or air through the primer.

It will thus be seen that the invention accomplishes its objects andwhile it has been herein disclosed by' reference to the details of apreferred embodiment, it is to be understood that such disclosure isintended in an illustrative rather than a limiting sense, as it iscontemplated that variousI modifications in the. construction andarrangement of the parts will readily occur to those skilledl in theart, within the spirit of the invention and the scope of the appendedclaims.

We claim:

l. A primer pump comprising a body member formed with a threadedy bore,a cylinder having an end inthreaded engagement with said bore, inletmeans in said member opening into said bore adjacent to and spaced froman end of the same for connecting said pump to a. supply of liquid, saidcylinder being formed with a series of circumferentially spaced portsadjacent to and spaced from said end thereof for communicating with saidinlet means in any position of angular rotation of said cylinder whenthreadedly engaged in said bore, a piston movably mounted in saidcylinder and adapted when positioned at said end of said cylinder tooverlie and close said circumferentially spaced ports, outlet means insaid member opening from said bore, and valve means in said member formaintaining unidirectional flow of said liquid in said pump. K

2. A primer pump comprising a body member provided with a cylinder,inlet means in said member opening at its inner end into said cylinderadjacent to and spaced from an end of said cylinder for connecting saidpump to a supply of liquid under pressure, a substantially cylindricalpiston movably mounted in said cylinder and having packing meansadjacent the opposite ends thereof, said piston being adapted whenpositioned at said end of said cylinder to close the inner end of saidinlet means and seal the same with said packing means positioned onopposite sides thereof for equalizing the liquid pressure on saidpacking means longitudinally of said piston, lubricating means mountedon and movable with said piston, said lubricating means beingimpregnated with a lubricant and located adjacent the end of said pistonopposite its liquid contacting end and between said end and the adjacentpacking means for preventing the pumped liquid from contacting anddissolving said lubricant, outlet means in said member opening from saidcylinder, and valve means in said member for maintaining unidirectionalflow of said liquid in said pump.

3. A primer pump comprising a body member formed with a threaded bore, acylinder having an end in threaded engagement with said bore, inletmeans in said member opening into said bore adjacent to and spaced froman end of the same for connecting said pump to a supply of liquid, saidcylinder being formed with a series of circumferentially spaced portsfor communicating with said inlet means in any position of angularrotation of said cylinder when threadedly engaged in said bore, asubstantially cylindrical piston movably mounted in said cylinder,packing means on said piston adjacent the inner and outer ends thereof,said piston being movable inwardly to bring the inner end thereof andthe inner packing means past said circumferentially spaced ports tooverlie and close the same, lubricating means impregnated with alubricant and mounted on said piston between the outer packing means andthe outer end of said piston for movement with said piston out ofcontact with said liquid in said pump for preventing deterioration ofsaid lubricant by the liquid pumped, outlet means in said member openingfrom said cylinder, and valve means in said member for maintainingunidirectional flow of said liquid in said pump.

4.` The combination comprising a cylinder provided with an inlet portopening through a side wall thereof,

and a piston slidable in said cylinder to cover and uncover said inletport, said piston having packing rings thereon, the wall of saidcylinder having a relatively thin portion adjacent said inlet port andhaving said portion ared outwardly for providing a smooth inner cylindersurface adjacent said port for Contact with said packing rings.

5. A cylinder having a side wall and a series of circumfercntiallyspaced inlet ports extending therethrough, said wall having relativelythin portions adjacent said inlet ports and having said portions aredoutwardly for providing a smooth inner surface for said wall adjacentsaid inlet ports.

6. The method of forming a cylinder member for pumps and the like havinga smooth inner surface and a port opening through a Wall thereofcomprising thc steps of forming a recess extending from the outside 8partially through thc wall of said cylinder member, boring an openingthrough the remaining wall of said cylinder member substantiallyconcentric with the center of said recess, said opening being smaller indiameter than snid recess for leaving a lip portion of reduced thicknessaround said opening, and flaring said lip portion outwardly into saidrecess for forming the cylinder member with a smooth inner surfaceadjacent said port.

References Cited in the le of this patent UNITED STATES PATENTS1,468,162 LeMaire Sept. 18, 1923 1,668,209 Jorgensen May l, 19282,070,805 Peterson Feb. 16, 1937 2,409,057 Meinke Oct. 8, 1946 2,419,192Anderson Apr. 22, 1947

